4 oz semi-sweet chocolate, chopped
1 stick unsalted butter, cut into tablespoon pieces, plus more for greasing
1 tsp vanilla extract
1/4 tsp salt, plus a pinch for the egg whites
12 Tbsp sugar, divided; plus more for dusting dish
5 large eggs, separated into yolks and whites, at room temperature for 30 minutes
1/4 c all-purpose flour
Put an oven rack in the middle position and preheat the oven to 350 degrees F. Butter a 6-cup souffle dish or casserole. Dust with granulated sugar.
Melt the chocolates and butter in a large bowl in a microwave-safe glass bowl in a microwave at 50 percent power for 2 to 3 minutes, stirring well every 30 seconds until the chocolate is melted and smooth. Cool completely.
Add vanilla, salt, and 6 tablespoons sugar. Add yolks 1 at a time, whisking well after each addition. Whisk in the flour.
Beat the whites with a pinch of salt in a bowl using an electric mixer at high speed until they hold soft peaks. Add the remaining 6 tablespoons sugar, 1 tablespoon at a time, beating until the whites hold stiff glossy peaks.
Whisk about 1/4 of the whites into the chocolate mixture to lighten the batter, then fold in the remaining whites gently but thoroughly. Pour the batter into the souffle dish, spreading it evenly.
Bake about 30 to 35 minutes or until the center is still jiggling and a toothpick inserted in the center comes out with moist crumbs adhering to it (It took me 35-40 min). Serve the souffle warm.
* Tips: when folding the egg whites into the chocolate mixture be very gentle. The more you add, the more careful you should be.I served mine with fresh strawberries. A light dusting of powdered sugar would be very pretty.